Taking All-Terrain Vehicle (ATV) as an example, typically, an ATV includes front wheels and rear wheels suspended on a front end and on a rear end, respectively, of a body frame. Handlebars and a seat are mounted on the frame. A power unit such as an engine is also mounted on the frame and generates the power required to propel the ATV. A transmission is provided to transfer the power generated by the engine to the front wheels, the rear wheels or both the front and rear wheels to drive the ATV.
Conventional transmission of ATV have a reverse idle gear and shaft disposed in a transmission housing wherein the shaft extends the full length of the transmission casing. The reverse idle gear shaft is typically supported on the left and the right ends of the transmission casing and extend fully therebetween. This typical gear arrangement requires additional space thereby increasing the size of the transmission casing and adding weight.
U.S. Pat. No. 6,799,485 discloses an engine/transmission assembly wherein the reverse idle gear shaft of the transmission gear mechanism is disposed within the transmission chamber and is supported on one side by a cover separating the transmission chamber from the crankcase thereby reducing weight. This arrangement only partially reduces the weight and size of the transmission and complicates the assembly of the components of the transmission.
Thus, there is a need for an improved transmission gear arrangement that alleviates some of the drawbacks of prior art transmission.